Conventionally, miniature unmanned aerial vehicles which are typified by unmanned helicopters for industrial use have been expensive and hard to obtain and manipulative skills have been needed to make them fly stably. However, a great advance has been made lately in improvement of a suite of sensors and software which are used for attitude control and autonomous flying of unmanned aerial vehicles and, consequently, maneuverability of unmanned aerial vehicles has improved significantly. Also, high-performance airframes of such vehicles have become available at a moderate price. Especially as for miniature multicopters, because their rotor structure is simple as compared with that of helicopters and they are easy to design and maintain, attempts are now made to apply multicopters to diverse missions in a wide range of fields, not only for hobby purposes.